Electrocardiograms in Athletes

[Electrocardiographic findings related to young Senegalese basketball players]

La pratique intensive et prolongée de sport peut induire des modifications cardiovasculaires et électrocardiographiques. L’objectif de ce travail était de décrire les modifications électrocardiographiques attribuables à la pratique de basket de compétition chez de jeunes noirs sénégalais. Les auteurs ont réalisé une étude prospective descriptive de l’électrocardiogramme (ECG) de surface de jeunes noirs sénégalais pratiquant le basket de compétition. Il s’agissait de 40 jeunes basketteurs, 20 filles et 20 garçons, dont la moyenne d’âge était respectivement de 17 ans ± 0,86 (extrêmes: 17 et 19 ans) et 15 ans ± 1,56 (extrêmes: 13 et 18 ans). La fréquence cardiaque était plus basse chez les garçons, 59 battements ± 9 battements (extrêmes: 42 et 85) que chez les filles 73 battements / min ± 11 battements (extrêmes: 50-95) (p = 0,0004). Les particularités suivantes ont été observées: des troubles de la repolarisation à type d’onde T négative de V1 à V4 dans 3 cas (7, 5%), une hypertrophie ventriculaire droite dans 1 cas (2,5%), une déviation axiale droite de QRS dans 1 cas (2,5%). La pratique intense et prolongée de basket entraîne des modifications électrocardiographiques chez le jeune noir sénégalais.

Cardiovascular Ultrasound Combined With Non-invasive Screening for the Detection of Undiagnosed Cardiovascular Disease: A Literature Review

Non-invasive screenings have been widely utilized in the United States and worldwide to provide early identification of cardiovascular disease, allowing for earlier diagnosis and treatment. Screening sonography detects valve disease, cardiac dysfunction, and carotid disease in 5% to 20% of the population. This review discusses the current data regarding cardiovascular screening, the methodologies, and the resources required for performance of screenings. Cardiac and carotid sonography is highly accurate and discovers cardiovascular diseases that impact quality of life and risk of future events. Screenings are performed in a variety of settings and accuracy depends on the quality of personnel performing the non-invasive testing, the equipment utilized, and the personnel interpreting the studies. Despite the potential benefit for disease detection, population screening to detect cardiovascular disease is not widely supported by national organizations due to the theoretical cost of further testing and lack of cost versus benefit data. Additional studies are necessary to compare costs and benefits of non-invasive cardiovascular screening in the community setting.

III SBC Guidelines on the Analysis and Issuance of Electrocardiographic Reports - Executive Summary

The third version of the guidelines covers recently described topics, such as ion channel diseases, acute ischemic changes, the electrocardiogram in athletes, and analysis of ventricular repolarization. It sought to revise the criteria for overloads, conduction disorders, and analysis of data for internet transmission. Resumo A terceira versão das diretrizes aborda tópicos recentemente descritos, como as doenças dos canais iônicos, alterações isquêmicas agudas, o eletrocardiograma dos atletas e análise da repolarização ventricular. Ela buscou rever critérios de sobrecargas, distúrbios de condução e análise de dados transmitidos via internet.

Abnormal heart rate recovery and deficient chronotropic response after submaximal exercise in young Marfan syndrome patients

BACKGROUND

Marfan syndrome patients present important cardiac structural changes, ventricular dysfunction, and electrocardiographic changes. An abnormal heart rate response during or after exercise is an independent predictor of mortality and autonomic dysfunction. The aim of the present study was to compare heart rate recovery and chronotropic response obtained by cardiac reserve in patients with Marfan syndrome subjected to submaximal exercise.

METHODS

A total of 12 patients on β-blocker therapy and 13 off β-blocker therapy were compared with 12 healthy controls. They were subjected to submaximal exercise with lactate measurements. The heart rate recovery was obtained in the first minute of recovery and corrected for cardiac reserve and peak lactate concentration.

RESULTS

Peak heart rate (141±16 versus 155±17 versus 174±8 bpm; p=0.001), heart rate reserve (58.7±9.4 versus 67.6±14.3 versus 82.6±4.8 bpm; p=0.001), heart rate recovery (22±6 versus 22±8 versus 34±9 bpm; p=0.001), and heart rate recovery/lactate (3±1 versus 3±1 versus 5±1 bpm/mmol/L; p=0.003) were different between Marfan groups and controls, respectively. All the patients with Marfan syndrome had heart rate recovery values below the mean observed in the control group. The absolute values of heart rate recovery were strongly correlated with the heart rate reserve (r=0.76; p=0.001).

CONCLUSION

Marfan syndrome patients have reduced heart rate recovery and chronotropic deficit after submaximal exercise, and the chronotropic deficit is a strong determinant of heart rate recovery. These changes are suggestive of autonomic dysfunction.

Screening of athletes: An electrocardiogram is not enough

Professional and amateur athletic training can cause tremendous overload of the cardiovascular system and thus become a trigger of serious and often fatal cardiac events in athletes with a previously undetected underlying cardiovascular disease. Therefore, every athlete should undergo a specialized diagnostic and qualification screening before a training program is prescribed or continued. However, it is still an unresolved issue which of the accessible diagnostic tools should be routinely applied in order to increase the safety of extreme physical training and reduce the risk of sudden cardiac death. Pre-participation athlete evaluation including a standard electrocardiogram (ECG), physical examination, and familial history of cardiovascular diseases is important, but does not always guarantee high diagnostic accuracy. Hence, the aim of this review article is to discuss the controversy over the usefulness of ECG for the detection of cardiovascular diseases in athletes as well as the views on athlete screening methods in Europe and the USA. Differential diagnostic options and screening schemes are also described in particular groups of athletes in reference to their age, cardiovascular risk factors, as well as intensity and type of sport discipline.

The Impending Dilemma of Electrocardiogram Screening in Athletic Children

Sudden cardiac death (SCD) affects 2/100,000 young, active athletes per year of which 40% are less than 18 years old. In 2004, the International Olympic Committee accepted the Lausanne Recommendations, including a 12-lead electrocardiogram (ECG), as a pre-participation screening tool for adult Olympic athletes. The debate on extending those recommendations to the pediatric population has recently begun. The aims of our study were to highlight the characteristics of the young athlete ECG, phenotypical manifestations of SCD-related disease in children, and challenges of implanting ECG screening in athletic children. A systematic review of the literature is performed. We searched available electronic medical databases for articles relevant to SCD, ECG, silent cardiac diseases, and athletic children. We focused on ECG screening and description in a pediatric population. We identified 2240 studies. Sixty-two relevant articles and one book were selected. In children, prepubertal ECG and the ECG phenotype of most SCD-related diseases differ notably from adults. The characteristics of the prepubertal ECG and of the phenotypical manifestation of SCD-related disease in children will result in less specific and less sensitive ECG-based screening programs. Those limitations advise against extending the adult recommendation to children, without further studies. Until then, history and physical exam should remain the cornerstone of screening for SCD-related pathologies in children.

The Impact of Sports Cardiology on the Practice of Primary Care Sports Medicine: Where Were We, Where Are We, Where Are We Headed?

This article is a commentary on the role of sports cardiologists in the athletic arena and the beneficial impact they offer sports medicine in the comprehensive care of competitive athletes. The focus is a dialogue on current recommendations for primary prevention of sudden cardiac arrest (SCA), incorporating elements of the preparticipation evaluation and continuing care of athletes with diagnosed heart disease (HD). The feasibility and potential advantages of implementing well-designed preparticipation cardiovascular screening programs and the role of sports cardiologists to educate primary care team physicians on secondary prevention of SCA and proper treatment of underlying HD are discussed.

Electrocardiographic changes in mitral valve prolapse syndrome

Introduction: Mitral valve prolapse syndrome (MVP) is the most common valvular abnormalityin the young and is correlated with increased frequency of cardiac dysrhythmias and sudden death.The aim of this study was to compare frequency of “early repolarization” in electrocardiogram(ECG) between MVP patients and healthy adults.

Methods: In this cross-sectional study, we compared ECG presentations of early repolarizationincluding notch in descending arm of QRS and J-point and/or ST segment changes in 100 patientswith MVP with 100 healthy individuals. MVP patients were referred to cardiology clinic withsymptoms of palpitation, chest pain or anxiety.

Results: The mean age in patients with MVP was significantly less than healthy subjects (29.5 ±9.3 years versus 31.0 ± 6.9 years in control group, P= 0.1967). We detected early repolarizationas a prevalent sign in ECG of patients which was a notch in descending arm of QRS and/or STsegment or J-point elevation seen in 74% of patients ( 51% in inferior leads and 23% in I and aVLleads) , whilst the same findings were seen in 8 men (8%) in control group (P= 0.0001).

Conclusion: Early repolarization in ECG presented as a notch in descending arm of QRS and/or ST segment or J-point elevation is more frequent in in young patients with MVP syndrome.

Sudden cardiac death in young athletes: preparticipation screening for underlying cardiovascular abnormalities and approaches to prevention

The study of sudden cardiac death (SCD) in athletes has received more interest in the medical and lay press over the past few years. Professional athletes represent ideals of fitness and health, and the sudden death of prominent athletes can come as a shock. Underlying occult cardiovascular disorders are the most common cause of SCD in athletes. Unfortunately, because these disorders rarely present clinically, their initial manifestation is often a fatal event. Due to this, much attention has turned to both primary and secondary prevention. Primary prevention includes preparticipation screening and secondary prevention includes having automatic external defibrillators available at sporting events. This article summarizes the most common causes of athletic-related cardiac arrest and evaluates the screening methods used to screen for these conditions. The general sentiment is that we need to more effectively identify athletes who are at risk for SCD, but how to do so using an efficient screening system and in a cost-effective manner have not been determined.

Twelve-lead electrocardiography in the young: physiologic and pathologic abnormalities

BACKGROUND/ OBJECTIVE: The purpose of the present study was to analyze the prevalence of physiologic and pathologic ECG abnormalities in a cohort of young conscripts that represents the whole young generation of today.

METHODS

ECGs of all Swiss citizens who underwent conscription for the army during a 29-month period were analyzed manually.

RESULTS

ECGs of 43,401 conscripts (mean age 19.2 ± 1.1 years) were analyzed; 158 conscripts were female. Incomplete right bundle branch block was found in 5870 (13.5%) and left anterior fascicular block in 360 (0.83%). First-degree AV block was present in 329 (0.8%) and Mobitz type I (Wenckebach) second-degree AV block in 3 (0.01%). Early repolarization was observed in 1035 (2.4%), T-wave inversion in 39 (0.09%), and minor T-wave changes in 182 (0.42%). Brugada-like abnormalities were observed in 6 (0.01%). None of the conscripts had atrial fibrillation or flutter.

CONCLUSION

ECG abnormalities can be found in a relatively large proportion of young individuals. Incomplete right bundle branch block, left fascicular block, and first-degree AV block are the most frequent findings. No conscript presented with atrial fibrillation or flutter.

Prevalence of electrocardiographic abnormalities in an unselected young male multi-ethnic South-East Asian population undergoing pre-participation cardiovascular screening: results of the Singapore Armed Forces Electrocardiogram and Echocardiogram screening protocol

AIMS

Resting 12-lead electrocardiograms (ECGs) have been employed in the pre-participation evaluation of young asymptomatic subjects to detect pre-existing heart diseases. Although the incorporation of routine ECG in pre-participation screening remains controversial, there is increasing evidence that cardiomyopathies and ion channelopathies have ECG changes as the initial manifestation. The causes of sudden cardiac death in young people show significant geographical variation. We aim to determine the prevalence and spectrum of ECG abnormalities in a young male South-East Asian population.

METHODS AND RESULTS

The Singapore Armed Forces Electrocardiogram and Echocardiogram (SAFE) protocol is an ECG-based pre-participation cardiac screening programme modelled after the Italian system. From October 2008 to May 2009, a total of 18 476 young male conscripts (mean age 19.5 years old, range 16-27) underwent mandatory pre-enlistment medical screening at a single medical facility. Subjects with abnormal ECG findings were classified into two groups: Group A had ECG changes that fulfilled a pre-specified checklist to screen for hypertrophic cardiomyopathy and were referred for transthoracic echocardiogram; Group B had other ECG abnormalities [such as Brugada pattern, Wolff-Parkinson-White (WPW) pattern, long QTc] and were referred for secondary screening at a tertiary institution. Of the 18 476 subjects screened, 7.0% (n= 1285) had ECG abnormalities. Of note, 19 (0.10%) had Brugada pattern, 25 (0.14%) had WPW pattern, and 31 (0.17%) had prolonged QT interval on ECG. The prevalence of ECG abnormalities was significantly higher in Chinese than in South Asians (7.2 vs. 5.7%, P= 0.003).

CONCLUSION

The prevalence of ECG abnormalities in a young, South-East Asian male population was 7.0%. There were significant ethnic differences, with ECG abnormalities more prevalent in Chinese than in South Asians (7.2 vs. 5.7%, P= 0.003). The inclusion of universal ECG, in addition to history and physical examination, may increase the sensitivity of a cardiovascular screening programme. Knowledge of the spectrum and prevalence of ECG abnormalities and disease conditions would be pivotal in designing customized screening programmes.

Overview of sudden cardiac death in young athletes

Sudden cardiac death is the leading cause of nontraumatic mortality in young athletes. The estimated incidence varies; however, recent studies have provided more accurate data. Most cases are attributed to silent hereditary or congenital cardiac disorders, many of which may be detected through preparticipation screening programs. This article provides a comprehensive review of the incidence and etiology of sudden cardiac death in young athletes, with practical advice regarding evaluation and management in light of a large number of recent advances. A brief outline of current perspectives on preparticipation screening programs and prevention is included.

Can we prevent sudden cardiac death in young athletes: the debate about preparticipation sports screening

All high school athletes in the United States require a preparticipation screening examination. The American Heart Association recommends a focused history and physical examination. The European Society of Cardiology recommends that all examinations include an electrocardiogram (ECG). We review the risks and costs of screening, discuss legal ramifications and analyse the ethical implications of these considerations. There are too many unknown about ECG screening to require it as routine testing for all high school athletes.

CONCLUSION

Doctors must inform young athletes and their parents about the option of ECG screening and about the debate over its efficacy. Patients and parents may then choose to have an ECG or not. Mandatory universal screening is not warranted at this time.

Electrocardiogram testing during athletic preparticipation physical examinations

CONTEXT

Sudden cardiac death (SCD) is a relatively rare yet unfortunate risk of athletic participation. To reduce the incidence of SCD, electrocardiogram (ECG) use during athletic preparticipation examinations (PPEs) has been proposed to detect underlying cardiac abnormalities.

OBJECTIVE

To estimate the effectiveness of ECG use during athletic PPEs.

DESIGN

Epidemiologic modeling.

POPULATIONS

Public high school athletes.

DATA COLLECTION AND ANALYSIS

Estimates of ECG sensitivity (70%) and specificity (84%) were drawn from the literature, as was the estimate of overall prevalence of cardiac conditions relevant to SCD (0.3%). Participation rate by sex was determined from National Federation of State High School Associations data. Participation by ethnicity was assumed to be proportionate to the public high school attendance rates for grades 9 through 12 (18.4% African American). Population-specific ECG effectiveness (positive predictive value), estimated total costs, cost per year of life saved, and cost to identify 1 additional case were computed. Total annual PPE screening costs reflected a cardiologist's office visit, including echocardiogram for those athletes with a positive ECG screen.

RESULTS

The model predicted that 16% of all athletes would be expected to have a positive ECG, but only 1.3% of athletes with a positive ECG would have a cardiac abnormality capable of causing SCD, including hypertrophic cardiomyopathy, structural defects, and various conduction abnormalities. Total annual cost estimates for ECG screening and follow-up exceeded $126 million. Average cost per year of life saved across groups was $2693, and the cost to identify 1 additional case averaged $100 827. Compared with females, males had both lower cost per year of life saved and lower cost to identify 1 true case. Similarly, black males exhibited lower costs than white males. Across groups, false-positive ECG screening exams accounted for 98.8% of follow-up costs.

CONCLUSIONS

Large-scale, mass ECG testing would be a costly method to identify athletes with cardiac abnormalities. Targeting high-risk populations can increase the effectiveness of the ECG for athletic PPE screening.

Cost-effectiveness of preparticipation screening for prevention of sudden cardiac death in young athletes

BACKGROUND

Inclusion of 12-lead electrocardiography (ECG) in preparticipation screening of young athletes is controversial because of concerns about cost-effectiveness.

OBJECTIVE

To evaluate the cost-effectiveness of ECG plus cardiovascular-focused history and physical examination compared with cardiovascular-focused history and physical examination alone for preparticipation screening.

DESIGN

Decision-analysis, cost-effectiveness model.

DATA SOURCES

Published epidemiologic and preparticipation screening data, vital statistics, and other publicly available data.

TARGET POPULATION

Competitive athletes in high school and college aged 14 to 22 years.

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTION

Nonparticipation in competitive athletic activity and disease-specific treatment for identified athletes with heart disease.

OUTCOME MEASURE

Incremental health care cost per life-year gained.

RESULTS OF BASE-CASE ANALYSIS

Addition of ECG to preparticipation screening saves 2.06 life-years per 1000 athletes at an incremental total cost of $89 per athlete and yields a cost-effectiveness ratio of $42 900 per life-year saved (95% CI, $21 200 to $71 300 per life-year saved) compared with cardiovascular-focused history and physical examination alone. Compared with no screening, ECG plus cardiovascular-focused history and physical examination saves 2.6 life-years per 1000 athletes screened and costs $199 per athlete, yielding a cost-effectiveness ratio of $76 100 per life-year saved ($62 400 to $130 000).

RESULTS OF SENSITIVITY ANALYSIS

Results are sensitive to the relative risk reduction associated with nonparticipation and the cost of initial screening.

LIMITATIONS

Effectiveness data are derived from 1 major European study. Patterns of causes of sudden death may vary among countries.

CONCLUSION

Screening young athletes with 12-lead ECG plus cardiovascular-focused history and physical examination may be cost-effective.

PRIMARY FUNDING SOURCE

Stanford Cardiovascular Institute and the Breetwor Foundation.

Athletes at Risk for Sudden Cardiac Death

High school athletes represent the largest group of individuals affected by sudden cardiac death, with an estimated incidence of once or twice per week. Structural cardiovascular abnormalities are the most frequent cause of sudden cardiac death. Athletes participating in basketball, football, track, soccer, baseball, and swimming were found to have the highest incidence of sudden cardiac death. Screening of athletes prior to participation in competitive sports usually falls short of recommended guidelines. Poorly defined legislation and the absence of a national standard for sports physicals have contributed to inadequate health screenings of athletes. This article will describe the incidence and causes of sudden cardiovascular death in young athletes as well as guidelines intended to prevent this unfortunate problem.

Practical management: a systematic approach to the evaluation of exercise-related syncope in athletes

Syncope and presyncope are relatively common presentations among athletes. The distinction between post-exercise and during-exercise syncope is critically important. While the great majority of these episodes occur just after exercise and are benign, syncope can be an indication of serious underlying cardiovascular disease if it occurs during exercise. Syncope presents a challenging differential diagnosis, as well as a daunting array of diagnostic tests and advanced imaging strategies. Sequencing a proper evaluation, and deciding who requires consultation and restriction, can be difficult for the medical provider. We present a systematic approach that assists the sports physician in arriving at a diagnosis and organizing an initial management strategy.

Return-to-play decisions in athletes with cardiac conditions

Many sets of guidelines written by experts in their fields can assist sports medicine physicians to make return-to-play decisions for athletes with known or suspected cardiac conditions. These guidelines can be divided into pre-participation screening guidelines, such as the 2007 American Heart Association (AHA) 12-element screening examination, and specific recommendations for those with heart disease or symptoms. Several important documents fall into the latter category. Among these are the 36th Bethesda Guidelines, the European Society of Cardiology Guidelines, the AHA Consensus Document for Young People with Genetic Conditions, the Heart Rhythm Society Guidelines, and the Guidelines for Masters Athletes. Guidelines are designed to enhance the sports medicine physician's probability of detecting heart disease and making wise participation and return-to-play decisions in athletes with high-risk cardiac conditions, such as hypertrophic cardiomyopathy, anomalous coronary artery, myocarditis, and valvular heart disease. Guidelines also aid in writing exercise prescriptions for those deemed too high risk for sports participation. Because the guidelines may not be entirely consistent on all topics, or based on opinion rather than research evidence, many cases require additional input from a cardiologist or electrophysiologist. Guidelines address not only specific disease entities, but also how corrective surgery, ablations, implantable defibrillators, or drug therapy can influence return-to-play decisions. They are updated as new studies become available to provide physicians with the most up-to-date information.

Normal resting electrocardiographic variants in young athletes

With a growing awareness of the tragedy of sudden cardiac arrest (SCA) in young athletes, more extensive pre-participation examinations are being performed prior to competitive sport participation. In addition to a history and physical, young athletes often have a 12-lead resting electrocardiogram (ECG) to better identify heart disease associated with SCA. Complicating this process is that certain "abnormal" resting ECG findings are considered normal variants in healthy children and young adults. The ability to recognize these normal variants is often useful in preventing excessive referral of patients to cardiologists for evaluation of resting ECG's that are benign variations of normal and in making sound decisions regarding appropriate clearance to exercise. This review describes these normal variants.

KEYWORDS

normal variants; early repolarization; athlete's heart.

Metallo-beta-lactamases: two binding sites for one catalytic metal ion?

During the past few years the results from molecular biological, biochemical, chemical, physical and theoretical approaches expanded the knowledge about metallo-beta-lactamases considerably. The main reason for the attracted interest is a persisting medical problem. Bacteria expressing metallo-beta-lactamases can be resistant to treatment with all the known beta-lactam antibiotics, and they are additionally invulnerable to combined treatment with inhibitors for the wider-spread serine-beta-lactamases. However, clinically useful inhibitors for metallo-beta-lactamases are not yet available. In spite of the rapidly expanding knowledge base a central question is still controversially discussed: is it the mononuclear, the binuclear or the metal-free state which might serve as the physiologically relevant target for inhibitor design? A summary of the present views of the roles and coordination geometries of metal ion(s) in metallo-beta-lactamases is combined with a discussion of the possibly variable metal ion content under physiological conditions.